What Is Ghostscript?
There are various products in the Ghostscript family; this document describes what they are, and how they are related.
Ghostscript is an interpreter for PostScript® and Portable Document Format (PDF) files.
Ghostscript consists of a PostScript interpreter layer, and a graphics library. The graphics library is shared with all the other products in the Ghostscript family, so all of these technologies are sometimes referred to as Ghostscript, rather than the more correct GhostPDL.
Binaries for Ghostscript and (seel below) GhostPDF (included in the Ghostscript binaries) for various systems can be downloaded from here. The source can be found in both the Ghostscript and GhostPDL downloads from the same site.
Prior to release 9.55.0 GhostPDF was an interpreter for the PDF page description language built on top of Ghostscript, and written in the PostScript programming language. From 9.55.0 onwards there is a new GhostPDF executable, separate from Ghostscript and written in C rather than PostScript.
This new interpreter has also been integrated into Ghostscript itself, in order to preserve the PDF functionality of that interpreter. For now, the old PostScript-based interpreter remains the default, but the new interpreter is built-in alongside it.
The intention is that the new interpreter will replace the old one, which will be withdrawn.
It is possible to control which interpreter is used with the NEWPDF command-line switch. When this is false (the current default) the old PostScript-based interpreter is used, when NEWPDF is true then the new C-based interpreter is used.
Historically, we’ve used GhostPDL as an umbrella term to encompass our entire line of products. We've now brought all these disparate products together into a single package, called, appropriately enough, GhostPDL.
When running on a printer (or server) GhostPDL now automatically detects the type of data being fed to it and processes it accordingly. The individual interpreters all plug into a top-level module that handles both automatic language detection and Printer Job Language (PJL) based configuration.
The exact set of interpreters present in an installation can be tuned by the integrator for their specific product/use cases.
In addition to our existing PDL modules (PS, PDF, PCL, PXL, and XPS) we have now added new modules to handle a range of common image formats. With these installed, GhostPDL will handle JPEGs (both JFIF and EXIF), PWGs, TIFFs, PNGs, JBIG2s, and JPEG2000s.
The source code for GhostPDL can be found on here.
GhostPCL is an interpreter for PCL™ and PXL files. This consists of an PCL/PXL interpreter hooked up to the Ghostscript graphics library.
Binaries for GhostPCL for various systems can be downloaded from here. The source can be found in the GhostPCL/GhostPDL downloads from the same site.
GhostXPS is an interpreter for XPS (XML Paper Specfication) files. This consists of an XPS interpreter hooked up to the Ghostscript graphics library.
Binaries for GhostXPS for various systems can be downloaded from here. The source can be found in the GhostXPS/GhostPDL downloads from the same site.
The set of truetype fonts in the urwfonts directory are necessary for the PCL/XL interpreter to function properly but they ARE NOT FREE SOFTWARE and are NOT distributed under the GNU GPL/AGPL. They can instead be redistributed under the AFPL license which bars commercial use.
If your copy of GhostPDL includes these fonts, you should have received a copy of the the Aladdin Free Pubilc License, usually in a file called COPYING.AFPL. If not, please contact Artifex Software, Inc. 1305 Grant Avenue - Suite 200, Novato, CA 94945 USA, or visit http://www.artifex.com/
PostScript is a registered trademark of Adobe Systems Inc.
PCL is a registered trademark of Hewlett-Packard Company.
Copyright © 2000-2021 Artifex Software, Inc. All rights reserved.
This software is provided AS-IS with no warranty, either express or implied. This software is distributed under license and may not be copied, modified or distributed except as expressly authorized under the terms of that license. Refer to licensing information at https://www.artifex.com or contact Artifex Software, Inc., 1305 Grant Avenue - Suite 200, Novato, CA 94945, U.S.A., +1(415)492-9861, for further information.
Ghostscript version 9.55.0, 27 September 2021